ATECC508A datasheet(69/109 Pages) MICROCHIP

69 / 109 page

1 byte

SN<8>

2 bytes

SN<0:1>

1 byte

Zero

2 bytes

SlotConfig<KeyID>

2 bytes

KeyConfig<KeyID>

1 byte

SlotLocked<KeyID> (Byte is 0x01 if SlotLocked Bit is set otherwise 0x00)

19 bytes

Zeros

32 bytes

TempKey.value

In all other cases, the message use to create TempKey is as follows:

32 bytes

OTP<KeyID> or Slot<KeyID> or TransportKey<KeyID>

1 byte

Opcode

1 byte

Param1

2 bytes

Param2

1 byte

SN<8>

2 bytes

SN<0:1>

25 bytes

Zeros

32 bytes

TempKey.value

9.7

GenKey Command

The GenKey command performs one or more of the following three operations:

Private Key Creation:

Creates a new random private key and writes that key into the slot specified by the KeyID

parameter. The EEPROM RNG seed will automatically be updated prior to the execution of this

command if it has not been already updated this power cycle.

Public Key Computation:

Generates an ECC public key based upon the private key stored in the slot defined by the KeyID

parameter. This mode of the command may be used to avoid storing the public key on the device at

the expense of the time required to regenerate it.

Digest Calculation:

GenKey can also combine a public key referenced by the KeyID parameter with the current value

stored in TempKey, calculate a SHA-256 digest of the resulting message, and place that digest

back into TempKey. This digest can be used as the message for an internal signature, or as a

component of a MAC computation. TempKey must be valid prior to digest calculation. If

KeyConfig.ReqRandom is set, then TempKey must have been created using the internal RNG.

The digest calculation operation can be performed by using either a public key computed from a private

key in a slot or by using a public key already stored in a slot. In the latter case, the appropriate checks for

prior authorization and limited use will be performed on the public key slot, and the remaining checks

indicated below will not be performed. When GenKey is used to calculate a digest on a public key slot, it

ignores the validity status of the public key.

ATECC508A

Security Commands

Datasheet Complete

DS20005927A-page 69

ATECC508A Arkusz danych(PDF) 69 Page - Microchip Technology

ATECC508A Arkusz danych(HTML) 69 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Arkusz danych Pobierz

Link URL